diff --git a/.github/workflows/libcxx_msan.yml b/.github/workflows/libcxx_msan.yml
deleted file mode 100644
index 6c5bde2..0000000
--- a/.github/workflows/libcxx_msan.yml
+++ /dev/null
@@ -1,36 +0,0 @@
-name: Build libc++ for MemorySanitizer
-
-on: [workflow_dispatch]
-
-jobs:
-  build-libcxx_msan:
-
-    runs-on: ubuntu-22.04
-
-    steps:
-    - name: Install dependencies
-      run: |
-        sudo apt update
-        sudo apt install -y git cmake ninja-build
-
-    - name: Install clang
-      run: |
-        wget https://apt.llvm.org/llvm.sh
-        chmod +x llvm.sh
-        sudo ./llvm.sh 17
-
-    - name: Build libcxx_msan
-      run: |
-        git clone --depth=1 https://github.com/llvm/llvm-project -b release/17.x
-        cd llvm-project
-        mkdir build
-        cmake -G Ninja -S runtimes -B build -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi" -DCMAKE_C_COMPILER=clang-17 -DCMAKE_CXX_COMPILER=clang++-17 -DLLVM_USE_SANITIZER=MemoryWithOrigins
-        ninja -C build cxx cxxabi
-        cd build
-        XZ_OPT=-e9 tar cfJ libcxx_msan.tar.xz include lib
-
-    - name: Archive libcxx_msan.tar.xz
-      uses: actions/upload-artifact@v3
-      with:
-        name: libcxx_msan
-        path: llvm-project/build/libcxx_msan.tar.xz
diff --git a/.github/workflows/test-sync.yml b/.github/workflows/test-sync.yml
index 2bcc666..7a3258f 100644
--- a/.github/workflows/test-sync.yml
+++ b/.github/workflows/test-sync.yml
@@ -67,7 +67,7 @@ jobs:
     - name: Install dependencies
       run: |
         sudo apt update
-        sudo apt install -y git build-essential cmake libuv1-dev libzmq3-dev libsodium-dev libpgm-dev libnorm-dev libgss-dev libcurl4-openssl-dev libidn2-0-dev
+        sudo apt install -y git build-essential cmake ninja-build
 
     - name: Install clang
       run: |
@@ -75,18 +75,23 @@ jobs:
         chmod +x llvm.sh
         sudo ./llvm.sh 17
 
+    - name: Build libcxx_msan
+      run: |
+        git clone --depth=1 https://github.com/llvm/llvm-project -b release/17.x
+        cd llvm-project
+        mkdir build
+        cmake -G Ninja -S runtimes -B build -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi" -DCMAKE_C_COMPILER=clang-17 -DCMAKE_CXX_COMPILER=clang++-17 -DLLVM_USE_SANITIZER=MemoryWithOrigins
+        ninja -C build cxx cxxabi
+        cd build
+        mkdir /tmp/libcxx_msan
+        cp -r include /tmp/libcxx_msan
+        cp -r lib /tmp/libcxx_msan
+
     - name: Checkout repository
       uses: actions/checkout@v3
       with:
         submodules: true
 
-    - name: Install libcxx_msan
-      run: |
-        mkdir /tmp/libcxx_msan
-        cp tests/src/libcxx_msan.tar.xz /tmp/libcxx_msan
-        cd /tmp/libcxx_msan
-        tar xvf libcxx_msan.tar.xz
-
     - name: Build libcurl
       run: |
         cd external/src/curl
diff --git a/cmake/flags.cmake b/cmake/flags.cmake
index 206f1fe..bd2c59e 100644
--- a/cmake/flags.cmake
+++ b/cmake/flags.cmake
@@ -76,7 +76,9 @@ elseif (CMAKE_CXX_COMPILER_ID MATCHES Clang)
 
 	set(WARNING_FLAGS "-Wall -Wextra -Wno-undefined-internal -Wunreachable-code-aggressive -Wmissing-prototypes -Wmissing-variable-declarations -Werror")
 
-	if (NOT DEV_WITH_MSAN)
+	if (DEV_WITH_MSAN)
+		set(OPTIMIZATION_FLAGS "-O2 -g")
+	else()
 		set(OPTIMIZATION_FLAGS "-Ofast -funroll-loops -fmerge-all-constants")
 	endif()
 
diff --git a/tests/src/libcxx_msan.tar.xz b/tests/src/libcxx_msan.tar.xz
deleted file mode 100644
index 405be3f..0000000
Binary files a/tests/src/libcxx_msan.tar.xz and /dev/null differ